Organic light emitting diodes (OLED), in particular stacked organic light emitting diodes, have hitherto been susceptible to roughnesses on the substrate surfaces or particles or inhomogeneities in the layers or the like which are incorporated into the layers of the organic light emitting diodes during processing. Such particles can lead to so-called latent short circuits (also designated as hotspots) in a respective organic light emitting diode, which initially inter alia cannot yet be detected, i.e. for example have no signature in infrared spectroscopy or have an increased electrical background signal. However, such hotspots can later lead to failures of the OLED during the operation of the OLED.
In order to avoid such spontaneous short circuits of stacked OLEDs, it is customary to provide a thick doped hole conductor layer (hole injection layer (HIL), also designated as hole transport layer (HTL)), usually having a layer thickness of several hundred nm, as a so-called shorts protection layer. Particles or the like are thereby intended to be leveled. However, suitable materials therefor are still very expensive and constitute a considerable cost factor. It generally holds true that the thicker the HIL layer, the greater the short-circuit resistance of the OLED.